Completion
Complete each
statement.
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1.
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An object becomes positively charged if it ____________________.
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2.
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Objects with unlike charges ____________________ each other.
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3.
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The farther you get from an electric charge, the ____________________ the
electric field.
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4.
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When an object is grounded, it becomes electrically ____________________.
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5.
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A simple circuit consists of a conductor, wires, and
____________________.
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6.
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As energy carried by a current increases, ____________________ increases.
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7.
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Electric energy can be stored by ____________________ charges.
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8.
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In a battery, electrons flow from the ____________________ terminal to the
____________________ terminal.
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9.
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When a wire is made thicker, its resistance ____________________.
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10.
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The unit used to measure electric current is the ____________________.
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11.
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According to Ohm’s law, voltage = ____________________ ´ ____________________.
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12.
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If a 1.5-V battery is connected in a simple circuit to a light bulb with a
resistance of 8 ohms, the amount of current flowing through the circuit is
____________________.
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13.
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In a series circuit, each device that is added to the circuit decreases the
____________________.
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14.
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If you multiply the voltage in a circuit by the current, you are finding the
____________________ of the circuit.
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15.
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Electric energy usage on your electric bill is measured in
____________________.
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Multiple Choice
Identify the
choice that best completes the statement or answers the question.
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16.
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____ is an example of a good electrical insulator.
a. | Aluminum foil | c. | Copper | b. | Silver | d. | Rubber |
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17.
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If an object loses electrons, the object will have a ____ change.
a. | positive | c. | neutral | b. | static | d. | negative |
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18.
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A simple complete circuit must have wires connected to a ____.
a. | switch | b. | switch and a conductor | c. | source of
electrons | d. | source of electrons and a conductor |
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19.
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A battery produces current electricity from ____.
a. | mechanical energy | c. | chemical energy | b. | static electricity | d. | strong nuclear
force |
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20.
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When you walk across a carpeted floor and then touch a metal doorknob, the
“shock” you may feel occurs because of a(n) ____.
a. | static discharge | c. | static charge | b. | electric field | d. | chemical
reaction |
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21.
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A measure of the potential energy available in a complete circuit is
____.
a. | current | c. | resistance | b. | power | d. | voltage |
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22.
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Dry skin is a good ____.
a. | conductor | c. | source of negative charges | b. | insulator | d. | source of positive charges |
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23.
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The negative terminal of a battery has ____.
a. | a pileup of positive charges | b. | a positive charge | c. | a pileup of negative
charges | d. | no charge |
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24.
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To prevent overloading in a parallel circuit, you could install a(n)
____.
a. | power meter | c. | electric generator | b. | fuse | d. | ground |
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25.
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When you rub a balloon on your hair, ____ go from your hair to the
balloon.
a. | electrons | c. | atoms | b. | protons | d. | neutrons |
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26.
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The filament in a light bulb is often made from tungsten wire because tungsten
is a ____.
a. | good conductor and has a high resistance | b. | good conductor and
has a low resistance | c. | good insulator and has a high
resistance | d. | good insulator and has a low resistance |
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27.
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In a battery, electrons flow from ____.
a. | one positive terminal to the other positive terminal | b. | the positive
terminal to the negative terminal | c. | the negative terminal to the positive
terminal | d. | one negative terminal to the other negative terminal |
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28.
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A wire that is ____ would have the greatest electrical resistance.
a. | short and thick | c. | long and thick | b. | short and thin | d. | long and thin |
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29.
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According to Ohm’s law, ____.
a. | current = voltage ´ resistance | c. | voltage = current
´ resistance | b. | power = current ´ voltage | d. | resistance = current ´
power |
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30.
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Two identical balloons are both rubbed with wool. If the balloons are brought
near each other, they will ____.
a. | attract each other | c. | have no effect on each other | b. | repel each
other | d. | ground each
other |
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31.
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When you use an electric appliance, the amount of electric energy used depends
____.
a. | only on the appliance’s power | b. | only on how long it is used | c. | on both the
appliance’s power and how long it is used | d. | on the appliance’s power but not how long
it is used |
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32.
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A series circuit is a circuit with ____ path(s) for the electric current to
follow.
a. | no | c. | more than one | b. | one | d. | infinite |
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Short Answer
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33.
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How are series and parallel circuits similar? How are they different?
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34.
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What are two ways an electric shock can harm the body?
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List the units used to measure each of the following.
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35.
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power of a microwave oven
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36.
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strength of a battery
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37.
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current flowing through a circuit
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38.
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resistance of a wire
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Essay
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39.
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What is the purpose of placing metal lightning rods at the top of tall
buildings?
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40.
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A person who has grasped a current-carrying wire might not be able to let go.
Why?
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Matching
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Match each term with the correct definition. a. | resistance | e. | insulator | b. | circuit | f. | series circuit | c. | conductors | g. | voltage | d. | electric field | h. | static charge |
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41.
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how much electric energy is in an object
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42.
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material in which electron cannot move easily from place to place
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43.
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buildup of electric charge on an object
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44.
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a continuously flowing closed loop
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45.
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measure of how difficult it is for electrons to flow through a material
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46.
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materials that allow electrons to move through them easily
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47.
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circuit that has only one path for the current to follow
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48.
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field from which electric charges are exchanged with another charge at a
distance
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Problem
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49.
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The current flowing through a lightbulb is 0.75 A and the voltage across the
lightbulb is 120 V. How much resistance does the lightbulb have?
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50.
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Suppose a wire with a resistance of 5 ohms is attached in a circuit to a 10-V
battery. How much current is flowing through the wire?
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51.
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An air conditioner uses 1,800 W of power when plugged into a wall socket that
operates at a voltage of 210 V. What is the current flowing through the air conditioner?
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52.
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What is the size of the current that flows through a 100-W lightbulb if it is
connected to a 110-V source?
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53.
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A television that requires an average of 0.40 A of current is operated on a
120-V outlet. What is the power usage of the television?
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